Who would do this?!?

This was one of the reasons we were glad we redid this. MC wiring (metal cased) was FORCED between the joists and the plaster. This created a gap between the lathe boards and the joists they were supposed to be attached to. After three years of a ceiling fan running and construction next door, more of the lathe boards came loose until the plaster cracked. The middle third of the ceiling was hanging on it's own weight. We were lucky it didn't crash down on us while sleeping.